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ericrost
 2 years ago
For Problem Lec.5.3.3: Functions on Lists Part 2 question 12, I don't understand why (length (cons y y)) is 4. For reference y => (1 2 3)
ericrost
 2 years ago
For Problem Lec.5.3.3: Functions on Lists Part 2 question 12, I don't understand why (length (cons y y)) is 4. For reference y => (1 2 3)

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teal
 one year ago
Best ResponseYou've already chosen the best response.0The list is ((1 2 3) 1 2 3), which is 4 items. The first list is only a single item, because it's in car.

dbastos
 one year ago
Best ResponseYou've already chosen the best response.1Like our friend above says, the first element is a single item. In Lisp, lists can contain any kind of elements. (Even other lists.) In that list of yours, the first element is a list (with 3 elements), but that list with 3 elements is /the first/ element of the list (cons y y). Does that clarify?
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